Characterization of a Holliday Junction-Resolving Enzyme from <i>Schizosaccharomyces pombe</i>

White, Malcolm F.; Lilley, David M. J.

doi:10.1128/mcb.17.11.6465

Cited by 65 publications

(52 citation statements)

References 45 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…cerevisiae and its ortholog from Sch. pombe (10,11,41). Poxvirus resolvases could have evolved from a prokaryotic source via a fungal intermediary; this makes an interesting parallel to the apparent common origin of the poxvirus and fungal RNA 5Ј-triphosphatases (42) and the specific relationships that are observed between poxvirus nucleoside triphosphate phosphohydrolase I and capping enzyme and the corresponding enzymes encoded in linear plasmids from yeast mitochondria (refs.…”

Section: Discussionmentioning

confidence: 99%

“…Although HJ-resolving activities have been found in extracts prepared from a wide variety of organisms, only enzymes from bacteria, bacteriophages, yeast mitochondria, and archaea have been genetically identified and characterized. The latter include Escherichia coli RuvC (3)(4)(5), bacteriophage T4 endonuclease VII (6), bacteriophage T7 endonuclease I (7,8), lambdoid prophage RusA (9), Saccharomyces cerevisiae mitochondrial CCE1 (10), Schizosaccharomyces pombe mitochondrial YDC2 (11), and Pyrococcus furiosus Hjc protein (12). These enzymes can be divided into two functional groups.…”

mentioning

confidence: 99%

See 1 more Smart Citation

Bacterial-type DNA Holliday junction resolvases in eukaryotic viruses

García

Aravind

Koonin

et al. 2000

Proc. Natl. Acad. Sci. U.S.A.

View full text Add to dashboard Cite

Homologous DNA recombination promotes genetic diversity and the maintenance of genome integrity, yet no enzymes with specificity for the Holliday junction (HJ)-a key DNA recombination intermediate-have been purified and characterized from metazoa or their viruses. Here we identify critical structural elements of RuvC, a bacterial HJ resolvase, in uncharacterized open reading frames from poxviruses and an iridovirus. The putative vaccinia virus resolvase was expressed as a recombinant protein, affinity purified, and shown to specifically bind and cleave a synthetic HJ to yield nicked duplex molecules. Mutation of either of two conserved acidic amino acids abrogated the catalytic activity of the A22R protein without affecting HJ binding. The presence of bacterial-type enzymes in metazoan viruses raises evolutionary questions. Homologous DNA recombination is a ubiquitous process that promotes genetic diversity and the maintenance of genome integrity in prokaryotic and eukaryotic organisms. The central intermediate in the recombination process is a four-way DNA junction usually referred to as a Holliday junction (HJ), consisting of two homologous duplex DNA molecules joined by cross-over strands (1, 2). Although HJ-resolving activities have been found in extracts prepared from a wide variety of organisms, only enzymes from bacteria, bacteriophages, yeast mitochondria, and archaea have been genetically identified and characterized. The latter include Escherichia coli RuvC (3-5), bacteriophage T4 endonuclease VII (6), bacteriophage T7 endonuclease I (7, 8), lambdoid prophage RusA (9), Saccharomyces cerevisiae mitochondrial CCE1 (10), Schizosaccharomyces pombe mitochondrial YDC2 (11), and Pyrococcus furiosus Hjc protein (12). These enzymes can be divided into two functional groups. Members of the first have RuvC as their prototype, include the resolvases from bacteria, mitochondria, and archaea, have high selectivity for HJs, exhibit sequence specificity for cleavage, and are thought to have roles in recombination and DNA repair. Members of the second group, composed of the bacteriophage enzymes, cleave a variety of branched DNAs, exhibit low sequence specificity, and have roles in recombination and the processing of DNA before packaging. Absent from either group, however, is a well-characterized HJ endonuclease from metazoa or their viruses.The poxviruses, of which vaccinia virus is the prototype, are large DNA viruses that replicate in the cytoplasm of infected cells and consequently provide a unique system for studying enzymes involved in RNA and DNA synthesis (13). Although the ability of poxviruses to undergo recombination has been long known (14), this process has not been separated from replication (15), and the viral proteins involved have remained elusive. An enzyme that cleaves HJs may participate in recombination as well as other steps in processing and packaging of poxvirus DNA. The genomes of poxviruses consist of a single linear doublestranded DNA molecule with covalently linked hairpin termini (16, 17) t...

show abstract

Section: Discussionmentioning

confidence: 99%

mentioning

confidence: 99%

Bacterial-type DNA Holliday junction resolvases in eukaryotic viruses

García

Aravind

Koonin

et al. 2000

Proc. Natl. Acad. Sci. U.S.A.

View full text Add to dashboard Cite

show abstract

“…Cleavage of a pair of symmetrical strands at the Holliday junction by a junction-specific endonuclease and sealing of the nicks by a DNA ligase generates classical "patch" or "splice" recombinant products. To date, six junction-resolving enzymes have been cloned representing eubacteria (RuvC), bacteriophage (T4 endonuclease VII, T7 endonuclease I, and lambdoid RusA), and eucarya (CCE1 from Saccharomyces cerevisiae and SpCCE1 from Schizosaccharomyces pombe) (1)(2)(3)(4). The detection of junction-specific endonuclease activities from eucaryal viruses and mammalian cells provides further evidence of the ubiquitous nature of resolvases (1).…”

mentioning

confidence: 99%

“…Even CCE1 from S. cerevisiae exhibits only weak sequence identity with its homologue from S. pombe, SpCCE1 (2)(3)(4). Despite this, the resolvases share certain physical and mechanistic attributes; e.g.…”

mentioning

confidence: 99%

See 1 more Smart Citation

Substrate Specificity of the SpCCE1 Holliday Junction Resolvase of Schizosaccharomyces pombe

Whitby

Dixon

1998

Journal of Biological Chemistry

View full text Add to dashboard Cite

SpCCE1 from Schizosaccharomyces pombe is an endonuclease that resolves Holliday junctions in vitro. SpCCE1 also binds and cleaves a range of other DNAs (Y-junction; flap; and flayed, nicked, and partial duplexes) with varying efficiency. Cleavage sites are always 3 of thymine nucleotides positioned at or close to the branch point or strand interruption. SpCCE1's favored substrate is the X-junction. Up to two dimers of SpCCE1 can bind concurrently to the same X-junction at its crossover point. From mixing experiments of SpCCE1 and the Escherichia coli RuvA protein, we show that each dimer of SpCCE1 binds to a different face of the X-junction and that both are seemingly competent for strand cleavage. We propose that this provides a mechanism whereby SpCCE1 can scrutinize all four junction strands simultaneously for cleavable thymine nucleotides. SpCCE1 appears to resolve X-junctions by a nick and counter-nick mechanism. Therefore, to ensure a high probability of bilateral strand cleavage, SpCCE1 has a relatively long lifetime on X-junctions. This mechanism has the drawback of limiting dissociation from noncleavable junctions. We discuss why this might not be a problem in vivo.Homologous recombination plays a central role in DNA metabolism; e.g. it provides a mechanism for the faithful repair of double strand breaks, facilitates the removal of lesions in single strand gaps, ensures the completion of DNA replication by helping to reform collapsed replication forks, and functions during meiosis to promote the correct segregation of homologous chromosomes. In addition, the genome rearrangements that are a consequence of recombination are an important component in the generation of genetic diversity.A key intermediate of the recombination reaction is the Holliday junction, which consists of two double-stranded DNA molecules linked by a reciprocal crossover of single strands. Cleavage of a pair of symmetrical strands at the Holliday junction by a junction-specific endonuclease and sealing of the nicks by a DNA ligase generates classical "patch" or "splice" recombinant products. To date, six junction-resolving enzymes have been cloned representing eubacteria (RuvC), bacteriophage (T4 endonuclease VII, T7 endonuclease I, and lambdoid RusA), and eucarya (CCE1 from Saccharomyces cerevisiae and SpCCE1 from Schizosaccharomyces pombe) (1-4). The detection of junction-specific endonuclease activities from eucaryal viruses and mammalian cells provides further evidence of the ubiquitous nature of resolvases (1).The known junction resolvases share little or no amino acid sequence similarity. Even CCE1 from S. cerevisiae exhibits only weak sequence identity with its homologue from S. pombe, SpCCE1 (2-4). Despite this, the resolvases share certain physical and mechanistic attributes; e.g. they are mostly small basic proteins (1), bind to DNA in a structure-specific manner (2-11), bind to junctions as dimers (3, 10 -13), distort the global conformation of the junction upon binding (9, 11, 14 -16), and resolve Holliday junctions by in...

show abstract

Holliday junction‐resolving enzymes—structures and mechanisms

Lilley

2017

FEBS Letters

View full text Add to dashboard Cite

Holliday junction-resolving enzymes are nucleases that are highly specific for the structure of the junction, to which they bind in dimeric form. Two symmetrically disposed cleavages are made. These are not simultaneous, but the second cleavage is accelerated relative to the first, so ensuring that bilateral cleavage occurs during the lifetime of the DNA-protein complex. In eukaryotic cells there are two known junction-resolving activities. GEN1 is similar to enzymes from lower organisms. A crystallographic structure of a fungal GEN1 bound to the product of resolution has been determined. These complexes are dimerized within the crystal lattice such that the strands of the products may be simply reconnected to form a junction. These structures suggest a trajectory for the resolution process.

show abstract

Characterization of a Holliday Junction-Resolving Enzyme from Schizosaccharomyces pombe

Cited by 65 publications

References 45 publications

Bacterial-type DNA Holliday junction resolvases in eukaryotic viruses

Bacterial-type DNA Holliday junction resolvases in eukaryotic viruses

Substrate Specificity of the SpCCE1 Holliday Junction Resolvase of Schizosaccharomyces pombe

Holliday junction‐resolving enzymes—structures and mechanisms

Contact Info

Product

Resources

About